Frequencies for first 10,000 rows of cigs variable in linkpe2009psden dataset :

 Cigarettes |
  Per Day U |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      3,083       30.83       30.83
          1 |         25        0.25       31.08
          2 |         14        0.14       31.22
          3 |         21        0.21       31.43
          4 |         16        0.16       31.59
          5 |         23        0.23       31.82
          6 |         16        0.16       31.98
          7 |          5        0.05       32.03
          8 |          3        0.03       32.06
          9 |          1        0.01       32.07
         10 |        125        1.25       33.32
         11 |          1        0.01       33.33
         12 |          3        0.03       33.36
         16 |          1        0.01       33.37
         18 |          1        0.01       33.38
         20 |         31        0.31       33.69
         30 |          6        0.06       33.75
         40 |          1        0.01       33.76
         99 |         46        0.46       34.22
          . |      6,578       65.78      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015